This publication discusses general problems related to the structure of current overload protection systems in high voltage (HV) electrical installations and introduces a family of new devices based on reed switch contacts, solid-state units, hybrid technology and automatic systems based on these components. It highlights their application in high voltage (5 to 100 kV) power supplies, power lasers and radar, RF-generators and protection systems for class 6 to 24 kV distribution networks. The author also discusses applications in power engineering, radio-electronic equipment, and industrial high voltage devices.